Periodic absorption refrigerating apparatus



Aug. 11, 193 w. B. NORMELLI PERIODIC ABSORPTION REFRIGERATING APPARATUS Filed June 29, 1932 5 Sheets-Sheet l A TTORNEYS Aug. 11, 1936. w. a NORMELLI PERIODIC ABSORPTION REFRIGERATING APPARATUS 5 Sheets-Sheet 2 Filed June 29, 1932 /NVEN TOR, WE N 01 7716111) Arra/?Mars Aug. ll, 1936. w B, NORMELL] 2,050,959

PERIODIC ABSORPTION REFRIGERATING APPARATUS Filed Jun 29, 1932 5 Sheets-Sheet 3 lid B. NORMELLI 2,050,959

PERIODIC ABSORPTION REFRIGERATING APPARATUS Filed June 29, 1932 5 Sheets-Sheet 4 /NVE'N 7'0/2 W B; NOI/naza) w. B. NORMEILL 2,050,959

PERIODIC ABSORPTION REFRIGRATING APPAATUS Filed Juhe 29, 1952 5 sheets-sheet 5 VVENTOR W %imella A Tra/?NE YS u Patenta& Aug. 1936 JNITED STATES' PERIODIC ABSORPTION REFRIGERATING APPARATUS i Wulif Berzelius Normelli, Berlin, Germany Application June 29, 1932, Serial No. 62.0,036 In Germany July 3, 1931 16 Claims.

My invention relates to 'a periodic absorption refrigerating apparatus and particular methods for controliing the temperature in a cooling chamber.

When operating absorption refrigerating apparatus a given temperature must be maintained inthe cooling chamber, suflicient to keep the products to be cooled fresh at all times. The refrigeration output required for this purpose is variabledepending upon the time of day and season. Care should be taken to attain the desired temperature in the cooling chamber by a supply of the necessary amount of cold. To this end, special control devices have men hitherto employed which afrect the production of cold according to the quantity of cold to be produced. With such control methods the apparatus are not fully utilized.

According to the invention the cold produced during the absorption period is stored up in a space insulated from the cooling chamber and thence, as may be required, transferred by special means to the cooling chamber. Since it is not necessary to influence the absorption process by control devices, the eiciency of the apparatus may thus be fully utilized. The total amount of cold capable of being supplied during the operating time of the refrigerator will be stored up in a cold accumulator and thence'transferred, as may be required, to the cooling chamber. The cold a'ccumulator `is preerably designed as a meltingchamber, the latter being preferably filled with a liquid, the freezing point of which lies below C. I

It is of particular advantage to equip the reirigerator with various generator-absorbers co- Operating with a common cold accumulator. The generator-absorbers are preferably operated in such a manner that when any one of the generator-absorbers is being operated as generator, the others are operated as absorbers. By selecting a convenient number of generator-absorbers and suitable dimensions, it is possible to design a refrigerator in such a manner that it has a uniform wattage, which is very important from the standpoint of tariff policy, since the public utilities lay stress upon the desirability of receiving from the consumers a possibly uniform' load. Particularly at night when the supply companies deliver current at low rates the generator absorbers mounted in the refrigerators may be fully utilized for the production of cold. The' cold may then be consequently withdrawn from thecold accumulator at any desired time.

In the accompanying drawings:

Fig. 1 is a vertical sectional View through one embodiment of my invention;

Fig. 2 is a sectional view of the control valve used in the circuit of the cold transfer system of the apparatus shown in Fig. 1;

Fig. 3 is a vertical sectional view ofla modified form of my invention;

Fig. 4 is a horizontal sectional view through the eyaporator shown in Fig. 3; Fig. 5 is a sectional view through the control device for the cold transfer system shown in Fig. 3;

Fig. 6 is a detail section of 'a part of the wall of the liquid accumulator used in the apparatus shown in Fig. 3; and

Fig. 7 is a diagrammatic sectional view showing a modified system of cold transfer for refrlgerators of the type disclosed. i

Referring' to the drawings, Fig. 1 shows a refrigerator which is equipped with two air-cooled periodic absorption refrigerating apparatusesoperating with solid absorption media. 1 and 2 denote the generator-absorbers containing a solid absorbent consisting, for instance, of calcium chloride saturated with ammonia. From the generator-absorbers the refrigerating medium passes during the generating period through the condensers 3 and 4 into the collecting vessels 5, 6 communicating with the -evaporator coils 1, B which project into a special space 9 designed as a meltng accumulator.

This space is preferably filled with a liquid which, owing to the evaporation of the cooling medium contained in the evaporator coils 'I and 8, freezes to a. solid mass which in turn melts upon application of heat supplied from the cooling chamber n. The cold accumulator is separated from the cooling chamber o by' an insulating layer ols. Both absorption refrigerating appa ratus operate alternately and store up the cold 'produced by the evaporator coils 1 and a in the cold accumulator 9. To transfer the cold thus stored up to the cooling chamber o, a system in which auxiliary liquid circulates is employed, con- 45 sisting of a condenser Il disposed in the cold accumulator 9 and of an evaporator coll !3 located in the cooling' compartment o. From the condenser ll, a conduit |2 leads to the evaporator coil s, while the evaporated auxiliary liquid passes from the cooling compartment o into the condenser H through the conduit M.

To maintain the temperature in the cooling chamber ll at a desiredvalue, a valve !5 is provided' in the conduit z and is controlled in acliquid is arranged below the valve seat.

cordance with the temperature prevailing in the cooling chamber ID. As soon as the temperature drops below the desired value the valve I5 closes so that the evaporation process of the auxlliary liquid is interrupted and a further supply of cold from the cold accumulator is consequently prevented. If a system for the transfer of an auxiliary liquid, as the one disclosed in Fig. 1 is employed with two connecting conduits between the evaporator and the condenser, the condenser ll is preferably dimensione'd in such a manner that when the valve !5 is closed, the total amount of liquid contained in the evaporator I3 may be taken up by the condenser so that a further transfer of cold is prevented.

The heating coils of both generator absorbers l and '2 are connected to a supply circuit 30, 3| through a contact making clock 29. This clock switches the heating coils on and oif periodically in such a manner that during the heating period of one of the generator absorbers, the other operates as absorber. In case suicient cold is stored up in the accumulator 9 a thermostat 32 arranged therein takes care that a further production of cold is prevented as soon as the temperature drops below a predeterm'ined value. By closing the contact of the thermostat, the switching in of the heating coils is prevented, so that a generating period is limited or one or more periods may be omitted.

It is preferable to use a liquid whose vapor pressure lies somewhat above the atmospheric pressure as' medium for transferring cold from the cold accumulator 9 to the cooling chamber lo.. For this purpose, ammonia or sulphur dioxide may, for instance, be utilized. The use of sulphur dioxide has the advantage that the conduits may be made of copper.

In Fig. 2 is shown a sectional view of the valve l5. The latter consists of a cylindrical casing IS in which the valve seat I'I is fixedly mounted. The conduit l2 leading from the cold accumulator 9. enters the casing s at a point above the valve seat I'I, and the discharge conduit !8 for the valve body I s cooperates with a cover plate 20 which is raised or lowered by a thermostatically `controlled bellows 2| in accordance with the temperature prevailing in the cooling chamber o. The cover plate 20,-the bellows 2| and a bellows 22 connected to the container and a base plate 25 enclose a space 23 completely filled up with a liquid, which space is expanded or coni tracted as a result of the temperature variations prevailing in the cooling chamber n. The cover I plate 20 and the valve body IS associated therewith are raised upon a rise in temperature against the pressure of a spring 24 so that in this case a flow of liquid takes place. To adjust to a predetermined temperature at which the valve should be operated anadjusting screw 26 is used which is rotatably mounted in a strap 21 attached to the casing IQ; By adjusting the screw 26, the bellows 22 is more or less compressed by means of a spring 23. At the same time this adjusting device protects the valve during the transport or The a conduit |03 into a condenser !04 arranged in the upper part of the refrigerator. From the condenser, the liqufied ammonia passes through a conduit !05 into a collecting vessel 105 which is surrounded with an aluminum foil irisulation lb'l. oa is a cold accumulator insulated from the cooling chamber !09. The cold produced by the apparatus is stored up in the accumulator and as may be required, transferred to the cooling chamber. An evaporator coil o is used for o the transfer of cold from the collecting vessel IOB. One end of the coil enters the collecting vessel at the lower part thereof, while the other end terminates above' the surface of the liquid. Besides, an ice container HI and a condenser l |2 are located in the cold accumulator !08. The evaporator coil u, the ice container ill and the condenser l l2 are provided with the common cooling ribs i !3 so as to ensure an efl'ective transfer of heat. The condenser ||2 communicates with an evaporator I|4 disposedin the cooling chamber !09 through a conduit IIS. A conduit s leading from a control member ll'l situated in the cooling chamber w! enters the condenser I|2 at the top.

The evaporator I|4 and the condenser |l2 are filled with a liquid to a marked level. The liquid evaporates in the evaporator l|4 at the temperature which prevails in the cooling chamber. The vapor bubbles rise to the condenser li! through the conduit 5 and are rapidlycondensed within the liquid. The heat of evapora-- tion is consequently absorbed from the cooling chamber os so that the desired cooling eflect is attained.

Fig. 4 shows a cross-section of the evaporator IM. The latter is surrounded by a pipe ll! open at both ends. A steel corrugated cirular I air grid I l9 is arranged in the space between ;both pipes so that the heat is conducted'from the outer 40 pipe s to the evaporator pipe II4. The air flows in the direction of the arrows as shown in Fg. 3 through the canals formed by the corrugated sheet and transfers the cold to the entire cooling chamber;

The control device ll'l serves to control the transfer of cold from the accumulator I to the. cooling chamber me. With the aid of the control member ll'l a decrease in pressure is caused in the system II2, ll4, l|5 upon a rise in temperature in the cooling chamber, whereas in the cooling chamber an 'increase in pressure takes place upon a drop of the temperature. Accordingly, the transfer of cold will be interrupted or initiated at a given cooling temperature depending upon the adjustment of the control member ll'l.

The control device II'I is shown in detail in Fig. 5. 325 is a container completely filled with a liquid. The walls of this container are formed 60 by a jacket 343 and the bellows` 334, 342. 33I. The inlet conduits 339 serve to charge this container. Both bellows 334 and 342 are secured to a plate 344. As the bellows are disposed closely to each other the control device is very sensitive to temperature variations. The pressure chamber 3|9 of the control member is fonned by a bellows 3|3, the outer wall of the jacket 343, the bellows 334 and by the plate 343. Both plates 344and 346 are provided with downwardly extending central enlargements in the form of oylinders so as to engage each other and the guide pin 345 of the adjustingscrew ll! is slidably movable in a central' opening of the plate 344.

This pin serves to limit the shoke of the con- 37 trol device in the upward direction. The control device is surrounded by a jacket 340 which is provided with two covers 34! and 341. The cover 34! is provided with a thread for the adjusting screw 3|5 which presses by means of a spring plate 335 a spring 3!6 against the closing plate 346 of the pressure chamber 3!9. The adjusting screw 3l5 is employed forta fine adjustment of the thermostatic device. The ibase plate 34'! is also provided with a thread for the adjusting screw 332 which presses with the aide: a spring plate 338 a spring 336 against the cover\-33`! to which the bellows- 33! and 342 are Secured. A coarse adjustment of the thermostatic device`iis eifected by the adjusting screw 332 which protects at the same time the control device from being injured during the transport or when out of operation. 3!! is a pressure conduit commu- I nicating with the pressure chamber 3!!! and is connected with the conduit !!6 entering the condenser !!2 at the top. Thus it will be seen that upon a rise in temperature in the cooling chamber the liquid placed in the container 326 expands' with the result that both bellows 334, 342, owing to the pressure exerted by the water, expand in the upward direction thereby causing the bellows 3|3 Secured to the plate 346 to also move in an upward direction. consequently, the 'pressure space 3i9 of the control device is enlarged, so as to cause a decrease in pressure which exerts an influence on the heat-.transfer system in the above-described manner through the conduit 3! l. Upon a decrease in temperature in the cooling chamber, the liquid in the container 326 contracts thereby causing the reverse efiect, i. e., an increase in pressure, in the pressure chamber 3! 9. The generator-absorber o shown in Fig. 3 is indireetly air-cooled during the absorption period. The generator-absorber !0! is surrounded by a cooling jacket !28, from the lower part of which a conduit !34 enters the container !20 disposed in the upper part of the refrigerator and to which a by-pass conduit !2! is connected. The conduit !22'leading from the container !23 also opens into the upper part of the container !20. The entire system for the transfer of heat consisting-of the cooling jacket !28 and the conduit !34, the container !20 and the control container !23 is filled up to a marked level with a liquid. On the top of the cooling jacket !28, a collecting space !24 is arranged, which communicates with the rising conduit !34 through a vapor discharge conduit !25 which extends downwardly from 'the collecting space !24 and then for some H distance upwardly in the conduit !34.

During the absorpton period, the liquid contained in the cooling jacket !28 is evaporated and collected in the collecting chamber !24. As soon as the vapor pressure overcomes the pressure of the liquid 'column placed above the outlet of the conduit !25 the vapor is blown oflf and rises through the conduit !34 to the container !20 in which the vapor is rapidly condensed within the liquid. The blowing oil of the vapor occurs at 'intervals, the durationof which depends upon the cooling time of the control container !23. The container !20 is arranged in a liquid accumulator !26 which is so designed (Fig. 6) as to be intensely cooled by air interiorly and exteriorly Not only the heat of absorption, but also that of condensation is absorbed by the liquid contained in the vessel !20 and then carried ofl` to outside atmosphere with the aid of the walls of the container !26. The condenser !04 for the refrigerating medium is wound around the inner walls of the central portion of the vessel !26 The vapors, rising through the conduit !34 to the container !20 and condensing in this container, heat particularly the upper portion of the liquid contained therein intensely so as to cause a circulation .through the by-pass conduit !2!.

. To insure also in this case an effective transfer of heat, the by-pass conduit !2! is connected* with a steel corrugated circular grid !35 which is sur- I rounded by an outer pipe !30, such as shown in Fig, 4 for the evaporator in the cooling chamber.

In order to prevent an unnecessary amount of heat of the system from being carried oil' to provided, in which a heating coil !21 is disposed which together with the heating coil !02 of the generator absorber is connected to the supply circuit !32, !33 through a contact making clock !29. In this manner, the liquid contained in the vessel !23 will evaporate so as to cause an excess pressure in the system so that an evaporation of the auxiliary liquid is prevented during the generating period. A thermostat !3I disposed in the cold accumulator !08 closes its contact as soon as the temperature drops below a predetermined value; thus interrupting the heating circuit, and thereby restricting or, if desired, completely eliminating the heating period. It is advisable to dimensi.-n the cold accumulator in such a manner that the stored up cold, in the event of a generating and cooling period being omitted is sufiicient to maintain the required cooling temperature in the refrigerator until a fresh *production of cold takes place after the neigt following generating period.

Fig. 7 shows a modified embodiment in which the temperature in the cooling chamber maybe .outside atmosphere, the control container !23 is I regulated in connection with the cold accumulator. 20! designates the cold accumulator and 202 the cooling chamber insulated therefrom. By means of an evaporator coil 203 cooperating preferably with a periodic absorption refrigerating apparatus, the coldis transferred to the accumulator. For the transfer of cold from the accumulator 20! to the cooling' chamber 202 two! auxiliary liquid systems are employed which are operated at different temperatures of evaporation of the auxiliary liquid contained therein. In this case the temperature of evaporation is preferably adjusted by the pressure of an inert gas contained in the system. However, v exterior mechanical means may also be employed in order to bring the temperature of evaporation to a desired value.

In the cold accumulator are placed two condensers 204 and 205 for'the auxiliary liquids and in the cooling chamber the corresponding evaporator coils 206 and 20'! which are connected to the condensers through the corresponding conduits 208, 209 and 2l0, 2!! respectively. It` is true that this -apparatus does not permit of an exactly uniform temperature being maintained in the cooling chamber, but the results attained thereby are satisfactory for various practical purposes. i The sensitivity of this appara tus to tem- 4 i 2,o5o,959

frigeration from the cold accumulator to the cooling chamber comprising a liquid circulating system in which the liquid is alternately evaporated and condensed and constitutes the heat conveying medium, and a control device arranged in said cooling chamber to influence the presure' in the transfer system aforesaid so as to cause an increase in pressure upon a drop of temperature prevailing in the cooling chamber and a decrease in pressure upon a rise in temperature in the cooling chamber.

2. A refrigerating system as claimed in claim l in which the control device includes a thermostatically controlled bellows arranged to reduce or increase the space in the heat transfer system incident to contraction or expansion.

3. A refrigerating system of the intermittently Operating absorption type comprising a generator-absorber, a condenser, a collecting vessel for the liquid refrigerant, anevaporator connected to said vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and Vice versa, a cooling chamber insulated from said vessel, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a medium in said cold accumulator for storing up the refrigeration produced during the absorption peri d and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumulator being so dimensioned that the refrigeration stored up during the absorption period suflices to maintain in the cooling chamber' the desired temperature also during the heating period.

4. Arefrigerating system of the intermittently Operating absorption type comprising a generator-absorber, a condenser, a collecting vessel for the liquid refrigerant, an evaporator connected to said vessel and connections for conveying the reirigerant from the generator-absorber to the evaporator and vice versa, a cooling chamber insulated from said vessel, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a cold storing up agent in said accumulator adapted to freeze during the evaporation of the refrigerant, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, the -cold accumulator being so dimensioned that the refrigeration stored up during the absorption period sumces to maintain in the cooling chamber the desired temperature also during the heating period.

5. A refrigerating system as set forth in claim 4 in which the refrigeration storing up agent employed has a freezing point lying below 0 C.

6. A refrigerating system comprising a plurality of intermittently Operating absorption apparatus which are alternately heated, each of said absorption apparatus comprising a generatorabsorber; a condenser, a collecting vessel for the liquid refrigerant, an evaporator connected to said collecting vessel* and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa, the collecting vessels of the single absorption apparatus being insulated from one another, a cooling chamber insulated from said vessels, a cold accumulator insulated from said cooling chamber and from said' ratus being in heat exchange relation with said cold accumulator, a medium in said'cold accumulator for storing up the* refrigeration produced during the absorption period, and means tor transferring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumulator being so dimensioned that 5. the refrigeration stored up during the absorption period sufiices to maintain in the cooling chamber the desired temperature also during the heating period.

' 7. A refrigerating system of the intermittently 0 Operating absorption type comprising a generator-absorber, a condenser, a collecting vessel ;for the liquid refrigerant, an evaporator connected to said vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa, a cooling chamber insulated fromsaid vessel, a cold accumulator in-' sulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a medium in said cold accumulator for storing up the refrigeration produced during the absorption period, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumulator being so dimensioned that the refrigeration stored up during the absorption period sufilces to maintain' in the cooling chamber the desired temperature also during the heating period, said means for the transfer of cold comprising a system which contains a heat transfer liquid, and means in said transfer system for controlling the transfer of heat between the cooling chamber and the cold accumulator.

8. A refrigerating system of the intermittently Operating absorption type comprising a generator-absorber, a condenser, a collecting vessel for' the liquid refrigerant, an evaporator connected to said vessel and connections for conveying' the refrigerant from the generator-absorber to the 40- evaporator and vice versa, a cooling chamber insulated from said vessel, a 'cold accumulator insulated both-from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a

medium' in said cold accumulator for storing up the refrigeration produced during the absorption period, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumulator being so dimensioned that the refrigeration stored up during the absorption period suffices to maintain in the cooling chamber the desired temperature also during the heating period, said means for the transfer of cold comprising a system in which B a liquid serving for the transfer of heat operates,

a conduit therefor, and a valve in said Conduit i which operates in accordance with the temperature prevailing in the cooling chamber.

9. A- refrlgeratingsystem of the intermlttently Operating absorption type comprising a generator-absorber, a condenser, a. collecting vessel for the liquid refrigerant, an evaporator connected to said vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa, a cooling c hamber insulated from said vessel, a cold accumulator in- -sulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, &7

medium in said cold accumulator for storing up the refrigeration produced during the absorption period, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumulator being so 7 aos oso 4 5 dimensioned that the refriger'aton stored up during the absorption period sufiices to maintain in the cooling chamber the desired temperature also during the heating period, said means for the transfer of cold comprising a system in which a liquid serving for the transfer of heat operates, a conduit therefor, and a valve in said conduit, and means for opening saidvalve upon a rise in temperature and for closing the same upon a drop in temperature in the cooling chamber.

10. A refrigerating system of the intermittently Operating absorption type comprising a generatOr-absorbe', a condenser, a collecting `vessel for the liquid refrigerant, an evaporator connected to said vessel and connections for 'conveying the refrigerant from the generator-absorber to the evaporator and vice versa, a cooling chamber insulated from said vessel, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulater, a medium in said cold accumulator for storing up the rerigeration produced duringthe absorption period, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber,`the cold accumulator being so dimensioned that the refrigeration stored up during the absorption period suflices to maintain in the cooling chamber the desired tem-- perature also during the heating period, said means for the transfer of ,cold comprising a system in which a liquid serving for the transfer of heat operates, a conduit therefor and a valve in said conduit, means for opening said valve upon a. rise in temperature and for closing the same upon a drop in temperature in the cooling chamber, and means for adjusting said temperatu'e responsive means so as to operate the'valve at a. predetermined temperature.

11. A refrigerating system of the intermittent ly Operating absorption type comprising a generator-absorber, a condenser, a collecting vessel for the liquid refrigerant, an evaporator connected to said vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa, a cooling chamber insulated from said vessel, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a medium in said cold accumulator for storing up the refrigeration produced during the absorption period, and means for transferring reirigeration as may be required from the accumulater to the cooling chamber, the cold accumulator being'so dimensioned that the refrigeration stored up during the absorption period suflices to maintain in the cooling chamber the desired temperature also during the heating period, said cold transfer means comprising a plurality of liquid circulating systems in which the liquid's circulate by alternate evaporation and condensation and which operate at diflerent temperatures of evaporation. g

12. A r'efrigerating system of the intermittently Operating absorption type comprising a generator-absorber, a condenser, a collecting vessel for the liquid refrigerant, an evaporator connected to said vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa, a cooling chamber insulated'from said vessel, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a

medium in said cold accumulator for storing u; the refrigeration produced during the absorption period, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumulatoi being so dimensioned that the refrigeration stored up during the absorption period suifices to maintain in the cooling chamber the desired temperature also during the heating period, a heating medium for the generator-absorber', a heating medium Conduit therefor, and a thermostat in said cold accumulator so adjusted as to interrupi said heating medium circuit upon a decreaseioi the temperature below a predetermined value, whereby a heating period is Shortened or completely cut ofl as may be required.

13. A refrigerating system of the intermittently Operating absorption type comprising a generator-absorber, a condenser, a collecting 'vessel .for

`the liquid'. refrigerant, an evaporator connected to said'vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa, a cooling chamber insulated from said vessel, a cold accumulator 'insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with said cold accumulator, a medium in said cold accumulator for storing up the refrigeration produced during the absorption period, and means for transferring refrigeration as may be required from the accumulator to the cooling chamber, a time control device for regulating' the generator heating, and means for interrupting the supply of the heating medium if the temperature in the cold accumulatordrops below a predetermined value, said cold accumulator being so dimensioned as to suflice in maintaining the temperature required in the cooling chamber if in the case of a heating period falling, the next followingproduction of cold is initiated after the next following heating period.

14. A refrigerating system of the intermittently perating absorption type comprising an aircooled generator-absorber, an air-cooled condenser, a collecting vessel for the liquid refrigerant, an evaporator connected to said vessel and connections for conveying the refrigerant from the generator-absorber to the evaporator and vice versa,` a cooling chamber insulated from said vessel, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relationwith said cold accumulator, a, medium in said cold accumulator for storing up the refrigeration produced during the absorption period, and means for transferring refrigeration as may be required i the generator-absorber to the evaporator and -vice versa, a cooling chamber insulated from said vess el, a cold accumulator insulated both from said cooling chamber and said collecting vessel, said evaporator being in heat exchange relation with 6 &050959 said cold accumulator, a medium in said cold accunulator for storlng up the refrigeration produced during the absorption period. and means for transterring refrigeration as may be required from the accumulator to the cooling chamber, the cold accumuiator being so dimensioned that the refrigeration stored up during the absorption period sumces to maintain in the cooling chamber the desired temperature also during the heating period.

16. In a refrigerating system of the periodic absorption type, a cooling chamber, a. cold accumulator insulated therefrom and having therein a medium for storing up the cold produced during the absorption period, an evaporator arranged in said cold accumulator, means for trans !en-ing refrigeration from the cold accumulator to the cooling chamber comprising a cold absorbing part arranged in the aceumulator aforesaid and a refrigeratlon supplying part 'in the cooling chamber, means for producing ice in the cold accumulator, and heat radiatng elements common to the evaporator, the cold absorbing part of the transer system and the ice producing means aforesaid.

WUlZFi?` BERZELIUS NORMELLI. 

